Electrical signaling or calling system.



No. 727,702. QPATENTBD MAY 12, 1903. 0.- B. SMITH.

ELECTRICAL SIGNALING 0R CALLING SYSTEM; APPLICATION FILED 111:0. 1a, 1899. nnnnwnn OUT. 22. 1902.

H0 MODEL.

avwenboz THE cams versus co mow-mun. WASHINGTON, o. c.

UNITED STATES .Iatented May 12, 1903.

PATENT OFFICE.

CHARLES E. SMITH, OF NEW YORK, N. Y.

SPECIFICATION forming part of Letters Patent N 0. 727,702, dated May 12, 1903.

Application filed December 13, 1899. Renewed October 22, 1902. Serial No. 128,247. (No model.)

To aZZ whom i2; may concern.-

Be it known that 1, CHARLES B. SMITH, a citizen of the United States, residing in New York city, borough of Manhattan, State of New York, have invented certain new and useful Improvements in Electrical Signaling or Calling Systems, of which the following is a specification.

My invention relates to a signaling or calling systemwhereby a large number of stations may be individually signaled over a limited number of wires.

In carrying out'my invention I provide a conductor that leads from a central office to a number of stations, for each of which stations a relayis provided and connected with said conductor, and from central a series or plurality of conductors also lead to said stations, and a signaling instrument in each of said stations .is connected with a conductor.

of said series. The relays located on the first-mentioned conductors areadapted to close circuits for said signaling instruments. At the centraloffice are located circuit-controlling devices for the conductors above mentioned, and the arrangement and operation are suchthat when the circuit of the firstmentioned conductor is closed all the relays connected therewithwill close the circuits of the corresponding signaliuginstruments, and thereupon current over the conductor that is connected with thesignaling instrument desired will cause the same to operate, and the other signaling instruments will not be operated, notwithstanding that the circuits of all such signaling instruments have been closed.

To increase the signaling capacity of the system without unduly increasing the number of signaling instrument conductors, I provide two or more conductors having relays at stations arranged as described with respect to the conductor first mentioned above, and the signaling instruments at such stations are connected with. the above-mentioned series of conductors in manner similar to that before described, and at the central office appropriate circuit-controlling devices are connected with the conductors. Thus current can be sent over either conductor having the relays to first close the circuits of the signaling instruments of the corresponding stations, and thereupon current is sent over the conductor that is connected with the signaling instrument desired to operate such instrument.

The invention further consists in' the novel details of improvement that will be more fully hereinafter set forth and then pointed out in the claims.

Reference is to be had to the accompanying drawing, which is a diagrammatic view of a signaling or calling system embodying my invention.

In the accompanying drawing the letter A indicates generally a central office at which are located appropriate devices for use in connection with my system. From the central office a conductor 1 leads through a plurality of stations B B B at each of which stations a circuit-closing relay 2 is connected with said conductor, said conductor being shown leading to ground at 1*,- the stations B B B thereby constituting a series of stations connected with conductor 1. From the central office a series or plurality of conductors 3 4 5 lead through said stations, there being as many conductors in said series as there are relays located on conductor-1. In each station B B B a signaling instrument 6 is located and connected with one of the conductors 3, 4, or 5. The instrument 6 in station B is shown connected with the conductor 3.

The instrument 6 in station B is shown with conductor 4, and instrument 6 in station B is shown connected with conductor 5', as by branch conductors 6 respectively. The circuits of the instruments 6 are normally open at the armature of relay 2, but are adapted to be grounded by said armatures, respectively. The arrangement is such that when it is desired to signal to one station of a series of stations the circuit of conductor 1 is closed to cause the relays 2 to close the circuits of conductors 3.4 5 of the corresponding instruments 6. By now sending current over either one of the conductors 3 4 5 the signaling instrument at the station B, B, or B may be operated. Then when-the circuit through conductor 1 is broken the circuits of the signaling instruments will be restored to their normal open conditions.-

Any suitable means may be provided at central A for closing the circuits of the conductors 1 3 4 5. I have shown circuit-closing devices or puslrbuttons Z) b 11 located at the central office and corresponding,respectively, to the stations B B B these circuitclosing devices being adapted to connect a source of current, as battery 7, with the conductors 1 and 3, 4, 5, respectively. The push-buttons b b b at central are adapted to throw ground 7 through battery 7 and conductors 1 and 3, 4, and 5, according to the station desired. The conductor 1 at central is shown connected with a contact 8, adapted to be engaged by a contact 9 to be operated by the plug or push-button of the circuit-closer b. The contact 9 is shown connected with bat tery 7 by conductor 10. The conductor 3 is connected with a contact 11, adapted to be engaged by a contact 12, arranged to be operated by the plug or push-button of the circuit-closer b, and the contact 12 is also shown connected with the conductor 10. The circuit-closers b and Z)? are arranged similarly to circuit-closer b and all connected with conductor 1; but the circuit closer I) is also connected with conductor 4 and the circuit-closer b is connected with conductor 5. Thus circuit-closer Z) puts ground and battery on wires 1 and 3, b on wires 1 and 4, and b on wires 1 and 5. If circuit'closer b be operated, current from battery 7 will pass over line I and energize relays 2, thus closing the circuits of signaling instruments 6; but as circuitcloser I? throws current from battery 7 only on conductor 3 the signaling instrument 6 at B will be the only one operated. If it had been desired to call either of the stations B or B instead of station B, the corresponding circuit-closer b or b would have been operated and the same eifect of closing the circuits for the several signaling instruments would have occured; but the circuit for operating the desired signaling instrument would have been closed only over the conductor 4 or 5 corresponding to the signaling instrument of the desired station.

From the foregoing it will be understood that any desired number of stations may be provided in a series connected with conductor 1, each station having a relay corresponding to the relays 2, and for each station in such series there will be a conductor corresponding to the conductors 3 4 5, connected with the signaling instrument in such station. Thus a single conductor, as 1, serves to close the circuits of all the signaling instruments in all the stations with which that conductor is connected, and each conductor of a series of conductors 3 4 5 are used to select and operate the signaling instrument at the station desired, and I therefore term the conductors 3 4 5 a series or plurality of selector-conductors.

I may increase the number of stations to any convenient extent without increasing the number of conductors contained in a series of selector-conductors. This may be accomplished as follows: In addition to conductor 1 I provide one, two, or more conductors 1 1, the conductor 1 passing through a series of stations 0 C G to ground and the conductor 1 passing through a series of stations D D D to ground, there being a number of stations in each series equal to the number of conductors 3 4 5 of the series of selectorconductors. In each of such stations the conductors 1" and 1 are provided with relays arranged similarly to conductor 1, the signaling instruments being connected in a similar manner to that before described to conductors 3 4 5. At the central office the conductor 1 is connected with circuitclosers c c 0 respectively connected with battery 7, and the conductor 1 is connected with circuitclosers d (2 (1 also respectively connected with said battery, all in manner similar to that described with respect to the circuitcloser 1). Thus each conductor 1 1 1 provides for closing the circuits of signaling instruments in the series of stations apportioned to such conductor, While one station of each series of stations is connected to one selectorconductor, as 3, another station of each series of stations is connected to another selectorconductor, as 4, and so on throughout the series of stations.

The operator at central merely closes the circuit of the conductors 1, l or 1 to which the relay of the desired station is connected, and also closes the circuit of theselector-conductor 3, 4, or 5 to which the signaling instrument of the desired station is connected. Instead of connecting the selector-conductors 3, 4, and 5 to battery 7 they may be connected to any other suitable source of current, such as a magneto-generator, the signaling instruments being adapted to operate by the current from such source.

I do not limit my invention to the details of construction shown and described, as they may be varied without departing from the spirit.

Having now described my invention, what I claim is-- 1. In a signaling or calling system, a condoctor to which a plurality of relays are connected, combined with a plurality of selector-conductors, a signaling instrument connected with each of said selector-conductors and each associated with one of the abovementioned relays, and means to operate the relays to close the circuits of all of said signaling instruments.

2. In a signaling or calling system, a central office from which a conductor leads, a plurality of relays connected with said conductor, a plurality of selector conductors also leading from central, a signaling instrument connected with each of said selectorconductors and each associated with one of said relays, and circuit-controlling devices at central to close the circuit of the first-mentioned conductor to operate all of its relays, and to close the circuit of either of said selector-conductors to operate the desired signaling instrument.

3. In asignaling or calling system, a central oflice from which a conductor leads, a plurality of relays connected with said conductor, a plurality of selector-conductors also leading from central, a signaling instrument connected with each of said selector-conductors and each associated with one of said relays, and circuit-controlling devices at central each apportioned toa different selectorconductor and all arranged in connection. with the conductor having the relays, where by when one circuit-closer is operated all of the relays close the circuits of all the signaling instruments and one signaling instrument will be operated by the closing of the circuit at central of its selector-conductor.

sociated with said relays, and-a plurality of circuit-closers connected with a source of current and each arranged to cause current to operate all of said relays and upon their operation to cause current to flow over the appropriate selector-conductor to operate the 7 corresponding signalinginstrument. A

6. Ina signaling or calling system, a plurality of conductors to each of which a plurality of relays are connected, combined with a plurality of selector-conductors corresponding to the number of relays on one of the firstmentioned conductors, and a signaling instrument associated with each of said relays.

7. In a signaling or calling system, a plurality of conductors to each ofgwhich a plurality of relays are connected, combined with a plurality of selector-conductors, a signaling instrument associated with each of said relays, the signaling instruments associated with the relays of one conductor each being of selector-conductors connected with signaling instruments associated with said relays, and a plurality of circuit-closers some of which are connected with one conductor having the relays and some connected with another such conductor, and all of said circuit-closers being connected with appropriate selector-conductors.

1 CHAS. B. SMITH.

Witnesses:

T. F. BOURNE, F. E. TURNER. 

